A study of platelet inhibition, using a 'point of care' platelet function test, following primary percutaneous coronary intervention for ST-elevation myocardial infarction [PINPOINT-PPCI]

Abstract

Background Rapid coronary recanalization following ST-elevation myocardial infarction (STEMI) requires effective anti-platelet and anti-thrombotic therapies. This study tested the impact of door to end of procedure ('door-to-end') time and baseline platelet activity on platelet inhibition within 24hours post-STEMI. Methods and Findings 108 patients, treated with prasugrel and procedural bivalirudin, underwent Multiplate1platelet function testing at baseline, 0, 1, 2 and 24hours post-procedure.Major adverse cardiac events (MACE), bleeding and stent thrombosis (ST) were recorded. Baseline ADP activity was high (88.3U [71.8-109.0]), procedural time and consequently bivalirudin infusion duration were short (median door-to-end time 55minutes [40-70] and infusion duration 30minutes [20-42]). Baseline ADP was observed to influence all subsequent measurements of ADP activity, whereas door-to-end time only influenced ADP immediately post-procedure. High residual platelet reactivity (HRPR ADP>46.8U) was observed in 75%of patients immediately post-procedure and persisted in 24%of patients at 2hours. Five patients suffered in-hospital MACE (4.6%). Acute ST occurred in 4 patients, all were <120mins post-procedure and had HRPR. No significant bleeding was observed. In a post-hoc analysis, pre-procedural morphine use was associated with significantly higher ADP activity following intervention. Conclusions Baseline platelet function, time to STEMI treatment and opiate use all significantly influence immediate post-procedural platelet activity.